Residents of Olympic bid city Tokyo celebrate while holding Tokyo signs after the announcement of the 2020 Summer Olympic Games host city at Komazawa Olympic Park in Tokyo, Japan.

The 2020 Olympics and Paralympics — to be held in Tokyo, Japan — are estimated to cost the national government seven times more than what was originally budgeted, Japanese newspaper The Mainichi reported on Friday.

Hosting the mega-events would cost Japan's national government 801.1 billion yen ($7.03 billion), the report said, citing the country's Board of Audit. That's the agency that reviews government expenditure.

Japan, the world's third-largest economy, had earlier estimated that the games would cost the central authority around 112.7 billion yen, according to the report.